Many search engine services, such as Google and Bing, provide for searching for information that is accessible via the Internet. These search engine services allow users to search for display pages, such as web pages, that may be of interest to users. After a user submits a search request (also referred to as a “query”) that includes search terms, the search engine service identifies web pages that may be related to those search terms. To quickly identify related web pages, the search engine services may maintain a mapping of keywords to web pages. This mapping may be generated by “crawling” the web (i.e., the World Wide Web) to identify the keywords of each web page. To crawl the web, a search engine service may use a list of base web pages to identify all web pages that are accessible through those base web pages. The keywords of any particular web page can be identified using various well-known techniques, such as identifying the words of a headline, the words supplied in the metadata of the web page, the words that are highlighted, and so on. The search engine service may generate a relevance score to indicate how related the information of the web page may be to the search request. The search engine service then displays to the user links to those web pages in an order that is based on their relevance.
Discussion threads are a popular way for people to communicate using the Internet. A particular popular type of discussion thread service is a web forum. A web forum is a web site that allows users of the web site to post information that is available to be viewed by other users of the web site. A discussion thread, such as a newsgroup, allows people to participate in a discussion about a specific topic. A discussion thread is typically initiated when a person creates an initial message directed to a topic and posts the message as a new discussion thread. Other persons can read the initial message and post response messages to the discussion thread. For example, the initial message may pose a question such as “Has anyone encountered a situation where the Acme software product aborts with error number 456?” Persons who want to participate in the discussion can post response messages such as “It happens to me all the time” or “I fixed the problem by reinstalling the software.”
A question-and-answer (Q&A) forum are tailored to such discussion threads that start with a question and may include one or more answers representing a Q&A form of a discussion thread. For example, a customer support group within a company that sells a certain software product may provide a Q&A for its customers to create and participate in discussion threads relating to the software product. A customer may initiate a discussion thread by posting an initial message that poses a question such as the one mentioned above. That question may be answered by the posting of a response message by another customer or a customer service representative. When posting answers to the question, each poster may designate that posting as having a suggested answer. Since the knowledge of the posters can vary significantly, a suggested answer may be wrong. A forum administrator may review the suggested answers and mark one or more postings as having a verified answer—that is, verified to be a correct answer. Also, a Q&A forum may have different discussion threads that are directed to essentially the same initial question. To assist customers in picking a discussion thread that provides the best discussion relating to the initial question, the forum administrator may designate some of those discussion threads as important.
The corpus of discussion threads of the company may provide a vast amount of knowledge related to problems and concerns that customers may encounter along with appropriate responses (e.g., answers to questions posed). The company may allow customers to search the corpus of discussion threads using a general-purpose search engine. A customer typically inputs a question in search of its answer. Such a general-purpose search engine, however, may not rank the search results in an order that is particularly helpful. For example, such a general-purpose search engine may rank a web page for the posting that contains the same question as its initial question relatively high and rank a web page for the posting that contains only the answer, but not the question, relatively low.